Process for dyeing fur pelts



Patented Mar. 27, 1928.

UNITED STATES 1,663,849 PATENT "OFFICE.

GEORGE T. LAEMMLE, OF NEW ROCHELLE, NEW YORK, ASSIGNOR TO BABNET LEATHER COMPANY, INC., 01 NEW YORK, Y., A CORPORATION OF DELAWARE.

PROCESS FOR DYEING FUR PELTS.

No Drawing. Application filed July 27,

This invention relates in general todyeing processes and more particularly has reference to a process for dyeing fur pelts.

Previous to this time, two methods known 5 as the brush and dip processes or modifications of these, have been generally followed in dyeing furs. In the brush process which Was the first of the methods developed, the

dye is usually applied in the form of a paste, with a brush, against the fall of the hair on the pelt. The dip process is acoo1nplished by immersing an entire fur including the skin in a bath of dye solution. A number of dyers employ both methods in the 1 process of a single fur pelt to obtain the desired end.

In certain types of pelts, such as calf skins, the hair grows in different directions from a center dead spot rather than in one direction from the head to the tail, as in the cases of most animals. This irregularity of growth has practically precluded the dyeing of these varieties of skins by the brush process, where the dye is applied against the fall of the hair, for the reason that proper application is obviously impossible. This has made it necessary to emplo the-dip method almost exclusively, attende with certain disadvantages to be hereinafter set forth.

In the brush process, it is necessary that great skill and care be exercised to regulate the depth to which the hair is dyed as the coloring material usually contains properties that are exceedingly destructive to the 35, roots of the hair and the skin. Also it is frequently necessary in certain types of dyes to make several applications of the dye, each coat of which must be individually applied and dried.

The quality of the dyeing of the hair of fur pelts colored by the dipping process is generally more satisfactory than that obtained by the brush process, but the skin is much more effected by the destructive action of the coloringmatter. In either process the dye which contacts with the skin has a tendency to loose the roots of the hair, so that the pelage easily peels off. The dyes also attack the tanning material so that the leather I is hardened and made to lose its stretch, be-

sides taking on an undesirable pl'umpness, especially in the dip process.

The excess dye stuff which remains on the hair after either the brushing or dlpping processes has a dangerous ettect on the mm- 1927. Serial No. 208,888.

cous membrane. While furs dyed by these methods are treated in various ways to eliminate the excess dye, the quantity of partially converted dyestuffs which cannot be re- .moved, exert a dangerous effect on persons '60 coming in contact with the fur.

An object of this invention is to provide a process for dyeing fur pelts by which the hair on the skins may be dyed in a single operation. 1

Another object of this invention is to provide a. process for dyeing fur pelts in which the hair may be uniformly dyed to any desired depth.

Still another object of this invention is to provide a process for dyeing fur pelts by which the individual hairs may be either partially or totally dyed without the dye reaching the roots or coming in contact with the skin.

A further object of this invention is to provide a process for dyeing fur pelts by which toxic effects of the dyes heretofore encountered may be eliminated.

With these and other ob'ects in view which may be incident to my improvements, the invention consists in the processes and materials to be hereinafter set forth and claimed with the understanding that the sev-. eral necessary steps in materials comprising my invention may be varied or modified in order, or changed in composition or proportion to any desired degree without departing from the spirit and scope of the appended claims.

Before fur pelts are subjected to a dyeing operation it is generally customary to first kill the hair to render the pelt more susceptible to absorption of the .d e and secondly to treat the killed fur wit a mordant to ,5 assist the fixation of the dye on the hair.

1n carrying out the dyeing process, according to this invention, the fur pelts having first been treated with a suitable killing agent are stretchedout ina suitable toggling apparatus to insure a flat surface free from pockets and to prevent buckling and sagging, and placed in any suitable stenciling apparatus, employing foraminous material, of any suitable variety, preferably mesh silk.

It is preferred, according to this invention, to employ oxidation colors in aqueous solution for dyeing the fur. By using these types of dyes, the coloring obtained may be varied over a wide range according to the no particular oxidizing agent employed and the concentration of the solution, and are not efl'ected by water. While alcoholic and other solvents may be used, it is deemed desirable in carrying out this invention to employ .an aqueous solution of ar a-phenylenediamine treated in a second solution with an oxidizing agent, although it may be exposed to air oxidation. Of the wide number of oxidizing substances, hydrogen peroxide is deemed the most suitable, although any other found desirable may be used. If it is desired, the para-phenylene-diamine may be replaced by any other suitable base, such as dimethyl-paraphenylene-diamine, or any one of the naphthalene diamines. Certain oxy and amide-oxy compounds may also be employed, such as para-amido phenol hydrochloride or para-toluene phenylene solphuric and varied in color by treatment with suitable metallic colors. By employ; ing these substances in the dyeing process; which are not actually dyes but coal tar intermediates, insoluble coloring products are formed by oxidation with suitable agents or-with air.

Any one of these intermediates in a ueous solution with a suitable amount of hy rogen peroxide or any other suitable oxidizing agent is thickened according to this inven tion by incorporating it with some-suitable viscous material soluble in water, although 1 if the dye is in a solution other than water,

a material soluble in the particular solvent should be employed. It has been found that gum tragacanth serves as an excellent binder, although a number of other substances, such as Irish moss or flax seed, may be employed if so desired. If gum tragacanth isemployed as the thickening agent, it is desirable to soak it in water previous to using and dissolve the dye in the paste that is formed. The paste made u in proportions to afford the mostworka le plasticity is placed on the screen and forced through the meshes of the silk with a squeegee in the conventional manner.

If an ordinary unthickened water solution is used, the dye will pass through the silk unimpeded and have no value, as it will easily penetrate through the pelage to the skin and the roots of. the hair. On the other hand if the solution is thickened to too great an extent, its passage through the silk will be so restricted as to lend little practicability to the operation. The viscosity, however, if properly regulated in practice will afford an even and uniform deposit of the dye on the hair and by slightlay varying the consistency the hair may be yed only on the tips or to any desired depth.

The dye forced through the skin and deposited evenly on top of the hair which has een previously killed so that it presents a stated, when this type of dye was employed in old processes, it has given rise to irritation of the mucous membrane and various pathological conditions, making'its use exceedingly dangerous. The first step in the oxidation of the para-phenylene-diamine isthe formation of quinone diimine, which is every unstable compound and even in aqueous solution decomposes or combines with itself. When para-phenylene-diamine is completely oxidized finally an azine compound is formed.

The reactions of other oxidation colors are similar to that of para-phenyl-diamine. In these dyes certain compounds or the position of the groups in the intermediate, afl'ord the variations in shades. The harmful efi'ects in the dye are caused by the quinone di-imine which is deposited in the form of particles on the surface of the hair from the dye solution instead of being absorbed by the hair fibers. This partially oxidized intermediate comes off as dust when the hair is disturbed.

By this invention the dye is applied to the hair so that it is almost wholly absorbed, with no appreciable-excess remaining to form dangerous residual particles. The fur pelts may be readily washed after the dyeing operation as the dye, as previously stated, is deposited in the form of an insoluble compound.

It is manifest that a pelt may be evenly dyed to any desired depth in following out this invention irrespective of the direction of the growth of the hair, as the fall of the hair is immaterial to this dyeing operation. It is also obvious that this invention is in nowise restricted to application with fur pelts such as calf skins and the like, but is adaptable also to all varieties of skins such as kid, as well as tanned leather without hair, or to various other materials such as felt, textiles, paper and the like.

There is accomplished by this invention a process for dyeing fur elts whereby an even deposit of dye may e applied on the hair to any desired depth without coming in contact with the skin or hair roots on the pelt and preventing the deposition of excess partially oxidized particles dangerous to health being deposited on the ham While I have shown and described the preferred embodiment of my invention, I wish it to be understood that I do not confine myself to the precise steps and materials, and compositions thereof herein set forth, as it is apparent that many changes and variations may be made therein by those skilled "inthe art without departing from the spirit of the invention, or exceeding the scope of the appended claims.

I claim:

1. A process for coloring fur pelts comprising applying color matter on the surface of the hair through foraminous material having relatively fine passages.

2.'A process for coloring fur pelts comprising forcing relatively thick coloring matter on the surface of the hair through foraminous material having relatively fine apertures.

3. A processfor coloring fur pelts comrising thickening coloring matter, and forcing the thickenedcoloring matter on the surface of the hair through foraminous material having relatively fine passages.

4. A process for coloringfur pelts comprising thickening coloring matter and forcing thickened coloring matter through a silk screen on the surface of the hair.

5. A process for coloring fur pelts comprising stretching the fur pelt, mixing an oxidizing agent with a dye base, thickening the dye base, and applying a uniform coating of the mix on the surface of the hair.

6. A process for coloring the hair on fur pelts to any desired depth comprising thickening coloring matter, forcing the thickened coloring matter on the surface of the hair through foraminous material having relatively fine passages, and regulating the plascoloring matter through a sil screen to apply a uniform coatingon the surface of the hair and regulating the plasticity of the coloring matter to vary the quantity passing through the silk screen and of proper viscosity to progress thedesired depth down the length of the hair.

8. A process for coloring the hair on fur pelts comprising applying coloring matter on the surface of the hair through foraminous"material having relatively fine apertures and regulating the quantity of the coloring matter applied to the hair.

9. A process for coloring fur pelts comprising stretching the fur pelt, thickening a dye "base and forcing the thickened dye base, on the surface of the hair through a silk screen to apply a uniform coating of an oxidation productdye.

10. A process for dyeing fur pelts comprising dissolving an aqueous solution of a dye base and an oxidizing agent in an aqueous solution of a viscous substance and applying the mix on the surface of the hair through foraminous material having relatively fine passages 11. A process for dyeing fur pelts with oxidation product dyes comprising dissolving an aqueous solution of a dye base and hydrogen peroxide in an aqueous solution of gum tragacanth, and forcing the mix through a silk screen by the action of a squeegee on the surface of the hair.

In testimony whereof I afiixmg si ature.

GEORGE J. E. 

